Year	Percent
1990	3.904
1991	3.994
1992	4.07
1993	4.125
1994	3.776
1995	4.4195
1996	3.7083
1997	3.5923
1998	2.5289
1999	1.9365
2000	2.1042
2001	2.3402
2002	2.9465
2003	3.0065
2004	2.9331
2005	3.5552
2006	2.7966
2007	1.9417
2008	1.8203
2009	1.9992
2010	2.5106
2011	2.5162
2012	2.1883
2013	2.8892
2014	3.1582
2015	3.7777
2016	3.6164
2017	3.4383